Electric heater



July29, 1930. I A. K. FISCHER ELECTRIC HEATER Filed July 5, 1929 2 Sheets-Sheet 1 lllllt' l ll'l'lnl A. K. FISCHER 1,771,752

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July 29, 1930.

Filod my a, 1929 2 shuts-shut 2 .l-llllll-lllllllll Patented July 29, 1930 UNITED STATES ADALBERT K. FISCHER, OF PHILADELPHIA, PENNSYLVANIA ELECTRIC HEATER Application filed July 5, 1929. Serial No. 375,985.

My invention relates to im rovements in electric heaters and it has or its object, broadly, to provide a construction of novel but simplified character whereby the cost of production and maintenance of repair are reduced, to a minimum.

It also is an object of the invention to provide an electric heater comprising a casing including a plurality of plates arranged in parallel relation to each other, and spacing means interposed between the said plates, the said plates and spacing means being united to form a hollow casing.

Another object of the invention is to pro- 5 vide an electric heater casing having a plurality of plates arranged in parallel relation to each other with their outer edges projecting to constitute heat-radiating fins, and spacing means interposed between the said plates, and means common to the said plates and spacing means for securing all of them together to form a unitary structure capable of being readily separated into its component parts.

A further object of the invention is to provide an electric heater the casing of which consists of a plurality of sheets arranged in parallel relation to each other, with separating or spacing means interposed between the said sheets at points inwardly of their outer edges, and means for securing any number of said sheet-separating or spacing means together. I I

Without attempting to point out at this time the further objects and advantages of the invention I shall proceed with a detailed description thereof wherein other ob'ects and advantages will be referred to speci cally or else will become apparent.

In order that the invention may be readily understood and its practical advantages fully appreciated reference should be had to the accompanying drawings, wherein I have illustrated certain forms of embodiment of the invention which at present are preferred by me. However, it will be understood that the inventionis susceptible of embodiment in other forms of construction than those shown and that changes in the various de- V tails of construction may be made within the scope of the claims without departing from the invention or the principle thereof.

In the drawings,

Fig. 1 is a view in longitudinal section of an electric heater embodying the invention, taken along the line 1-1 of Fig. 2;

Flg. 2 is a longitudinal sectional view taken along the line 22 of Fig. 1;

Fig. 3 is a transverse sectional view taken along the line 3-3 of Fig. 1;

Fig. 4 is a view in perspective of one of the fin plates;

Fig. 5 is a similar view of a member employed for separating or spacing the fin plates;

Fig. 6 is a longitudinal sectional view showing a modified construction of casing for an electric heater embodying my'invention,

the said view being taken on the line 66 of Fig. 7.

Fig. 7 is a longitudinal sectional view taken on the line 77 of Fig.6; V

Fig. 8 is a transverse sectional view taken on the line 8-8 of Fig. 6';

Fig. 9 is a longitudinal sectional view of another modified construction of easing embodying the invention, the said view being taken on the line 9-9 of Fig. 10;

Fig. 10 is a longitudinal sectional View taken on the line 1010' of Fig. 9; and so Fig. 11 is a transverse sectional view taken on the line 1111 of'FigQt).

In the several forms of construction it will be noted that I have provided lates (hereinafter referred to as fin plates which are held in spaced relation to each other by separating or spacing means of one kind or another. It will be apparent, therefore. that in the several forms of heater casing embodying the invention the principle of construction and operation is the same. I

- Referring first to Figs. 1 to 5 of the draw ings, it will be noted that in the construction of heater there shown I have provided a plurality of plates 1 whichI shall denominate fin plates, which, as shown, are of rectangular shape, but they may be of any other shape preferred. Each of the plates 1 is provided with a central opening 2, which openings are of rectangular shape corresponding to the shape of the plates. is stated with respect to the plates, the sai openings may be of any shape desired. In the completet tructure as illustrated the plates 1 are held in spaced p rallel relation to each other by means of rectangular shaped spacing members 3 the dimensions oi which in both directions are substantially less than the corresponding or similar dimensions of the lin plates 1. The spacing members 3 may be described as being tlat and they, as are the plates 1, are provided with central rectangular shaped openings, as shown at These openings are of the same size as the openings 2, so that when the plates 1 and the spacing members 3 are assembled as shown in Figs. 1

and 3 of the drawings they cooperate to term or provide a chamber rectangular shape in cross section, as indicated in the drawings. The chamber provided by these assembled plates 1 and spacing members 3 closed at its opposite ends by means of relatively narrow cover plates ti and 7. These latter plates, together with the tin plates 1 and the spacing members 3, are secured together in contactual relation to each other, as shown in Figs. 1 and 3, by means ct tie-rods which extend through registered openings 11 provided in the fin plates 1, the spacing devices 3 and the cover plates 6 and 7 upon the opposite sides of the structure. The oppon ends of the tie-rods 10 are scrcw-th for the reception of binding and clamping nuts 12. It will be apparent that the number of fin plates 1 and spacing members 3 may be varied either by increasing or diminishing the number, as indicated in 1 and 3, and that the lengths of the tie-rods 10 may be correspondingly changed. It will be seen that the tin plates 1 and spacing members S (which are likewise in plate form but of considerably greater thickness than the fin plates 1) are secured together in direct contact with each other, and that no packing of any kind is required.

For the purpose of supporting the heating elements within the chamber of the easing I have provided within the said chamber at the opposite edges thereof bars of electric insulating material, which bars are supported upon rods 21 the opposite reduced end portions 22 of which project into openings in the cover plates 6 and 7 and are thereby supported by the said cover plates. Resistance wires 23 are located within the chamber of the casing and are connected at their opposite ends to blocks of conducting material which are secured to and supported upon the bars 20 of insulating material. The said resistance wires 23 may be connected in series, as indicated, or in parallel according to conditions. Current is conducted to and from the said wires through conducting means indicated at 25, the latter having connection with the wires through a connection or junction box 26 mounted upon the cover plate 6 in adjoining opposed relation to one end of one oi the bars 20.

It will be apparent that upon removing either one of the fastening or retaining nuts 12 from the rods 10 the heater may be disassembled readily, and it also will be apparent that the parts 1, 3, 10, and the heating elements of the structure may be readily assembled and fastened together.

In the construction as illustrated in Figs. 6 to S of the drawings 1 have shown the central. rectangularly shaped openings 29 of the fin plates 30 as being provided with laterally extending flange 31, which flanges are adapted to cons itute the spacing means between the said tin plates 3 The outer edge of the Flange of one plate contacts with the ad oinmg side of the ad oining fin plate 30, as lndicatcd in Figs. 6 and T of the drawings. These tin plates 30 when placed in adjoining parallel relation to each other as shown in Fig. 6. cooperate to produce a chamber open at both ends, which chamber is closed by means of plates 33 and 3-1. The former plate, which is in contact with an adjoining in plate 30, of a length and width only requisite for closing the adjoining end of the chamber 32, while the opposed closing plate 34 which is seated against the outer edges of the flange ot the adjoining in plate 30 is of a length and width corresponding to the fin plates 30. The fin plates, together with the cover or closing plates 33 and are held detachably t0- gcther by means of the fastening and clamping nuts upon the opposite screw-threaded ends of the tie-rods 36 which operate in identically the same manner as the tie-rods 10 for holding the fin plates 30 and spacing members 3 in assembled contactual relation, as indicated in Figs. 6 and T of the drawings.

In the modified construct-ion of my invention as illustrated in Figs. 9, 10 and 11 1 cmploy two sets or groups of fin plates 40 and ll each of which consists of a relatively narrow plate with one edge thereof bent and extended laterally and outwardly, as indicated at i2. The outwardly extending part 43 of the laterally and outwardly bent portion 42 of each plate 10 and 41 is substantially parallel with the main or body portion thereof. hen the plates 10 and d1 are assembled to form the respective groups or series it will be noted that the laterally and outwardly bent portions thereof are interposed between adjoining plates and that the outwardly bent portions are in contact with such adjoining plates. This relationship is clearly shown in Fig. 11 of the drawings. These respective groups of plates 10 and =11 are held together by tie-rods 4-5 which extend through openings provided in the said plates and also in the outwardly bent portions -13. The respective groups of plates 4.0 and 41 are fastened or united together by means of Cover lid Pit)

which the opposite ends of the tie-rods project. Clamping nuts are provided upon the outer ends of the said tie-rods and operate to hold the said groups of plates and the plates 46 and 47 in assembled relation to each other. The plates 48 and 49 previously referred to extend in planes at right angles to the planes of the plates 40, 41, 46, and 47 and are secured in position in any desired manner, perferably by tie-rods, which, however, are not shown.

It will be observed that in the several forms of construction the heat-radiating fin plates are assembled in spaced relation to each other, being held in such spaced relation by spacing means of one kind or another, and that the assembly of the said fin plates and the cover plates associated therewith combine or cooperate to produce a casing having a closed chamber within which the heating coils or elements are mounted. The said heating elements are not in contact with the casing, from which it follows that the heat is transmitted to the material of the casing by radiation and by convection.

By my invention I am enabled to provide a casing for an electric heater in which the heat-radiating fin plates are held in assembled relation to each other by tie-rods or the like. It will be apparent that by the employment of tie-rods, as shown and described, the plates may be readily assembled and united to form a unitary structure and also that they may be readily disassembled and separated from each other if occasion therefor should arise. It also will be apparent that by the removal of either one of the readily removable cover plates to which reference has been made, access may be had to the heating means for repair or for any other purpose. v

Having thus described my invention, what I claim and desire to secure by Letters Patent is: a

1. An electric heater, comprising a casing consisting of heat-radiating fin, plates each having a central opening therethrough, spacing plates located between said fin plates to hold them in spaced substantially parallel relation to each other, said spacing plates being of less length and width than said fin plates and having central openings there through in registry with the central openings in said fin plates, the said fin plates and spac-' IIIGflIIS extending through said holes for binding the said fin plates and spacing plates together.

' 2. Anrelectric heater, comprising a casing consisting of heat-radiating fin plates each having a central opening therethrough, spacing means located between said plates to hold them in spaced relation to each other, the said spacing means being located at the inner edges of the said fin plates and cooperating therewith to provide the inclosing wall of the said casing surrounding the chamber thereof, the length and width of said spacing means being less than the'length and width of said fin plates, cover plates provided over the opposite ends of said chamber, and tying means extending through the saidcover plates and through the fin plates for securing and hold-' ing the same in assembled relation.

3. An electric heater, comprising a closed casing consisting of fin plates located in spaced parallel relation to each other, spacing means located between the said fin plates at the inner edges thereof and cooperating with the inner edge portions of the said plates v to provide the wall of the said casing which surrounds the chamber thereof, the length and width of said spacing means being less than the length and width of said fin plates, cover plates for closing the opposite ends of the said chamber, the said cover plates being supported in parallel relation to the said fin plates, and means for-fastening the said fin plates, spacing means and cover plates together.

4. An electric heater, comprising a casing which consists of a plurality of substantially parallel fin plates having openings located centrally thereof, spacing plates having dimensions substantially less than the dimensions of the said fin plates, and having openings therein with dimensions substantially equal to the dimensions of the openings of the said fin plates, the said spacing plates bein located between the said fin plates to hold the same in spaced relation to each other, the said fin plates and spacing plates having holes therethrough, cover plates for closing the opposite ends of the chamber formed by the inner edges of the said fin plates and spacingplates, said cover plates also having holes therethrough, the holes in the several plates being in registry with each other when the said plates are in assembled relation, and tierods extending through the said holes and operating to bind all of the said plates together.

5. An electric heater, comprising a casing consisting of a plurality of fin plates arranged in substantially parallel relation to each other, spacing means interposed between the said plates and located at the inner edges thereof to hold the same in spaced relation to each other, cover plates for closing the opposite ends of the chamber formed by the 3 said fin plates and the said spacing means, means for holding the said fin and cover plates and the said spacing means in assembled relation, bars of electric insulating material supported at the opposite edges of the chamber of the said casing, and electric heating elements supported at their opposite ends upon the said bars.

6. [in electric heater, comprising a casing consisting of substantially parallel heatradiating fin plates, spacing means located at the inner edges of said plates and interposed therebetween for holding the said plates in spaced relation to each other, the said plates and spacing means cooperating to form a chamber open at its opposite ends, cover plates for closing the opposite ends of said chamber, tie-rods extending through the said fin plates and the said cover plates for holding the same in assembled relation, rods extending through the chamber of the said casing and supported at their opposite ends upon the said cover plates, the said rods being located at the opposite edges of the chamber of the said casing, electric insulating members mounted upon the said last mentioned rods, blocks of electric current-conducting material mounted upon the said members, and elect ic heating elements supported at their opposite ends upon the said blocks.

In testimony that I claim the foregoing as my invention I have hereunto signed my name this 2nd day of July, A. D. 1929.

ADALBERT K. FISCHER. 

